1. Field of the Invention
This invention is directed to a valve assembly designed for use in musical instruments, such as trombones and other members of the "brass" or "wind" family. The valve assembly of the present invention is structured to permit the selective directing of air flow along predetermined ones of a plurality of flow paths in order to selectively vary the length of the path the air travels from the air inlet or mouth piece to the air outlet or bell of the instrument, and therefore, extend the lower range of the instrument and allow for a selective change in the pitch and tonal quality offered by the musical instrument.
2. Description of the Related Art
Air flow valves having a variety of different configurations, structures and other operative features have been used on musical instruments in the brass and/or wind family for over a hundred years in order to provide the musician playing the instrument with a greater range in terms of both pitch and tonal quality. Generally speaking, such flow path selector valves, particularly of the type used with brass-wind instruments, are either of the rotary type or alternatively, are of the piston and cylinder type. In the latter category, also commonly referred to as Perinet valves, a piston is longitudinally slidable within a cylinder against a biasing force. The piston normally has both a longitudinal bore and transverse bore which enable air to be conducted along a shorter or longer path of travel, in order to selectively vary the tonal quality of the instrument. Passages formed in this type of valve are round in cross section, and thereby, permit free flow of air therethrough which is desirable for achieving increased sound volume and a high quality tones. However, one recognized disadvantage for this type of valve is a relative long actuating stroke and the existence of high inertia in operating such valves. This limits the actuation time of the valve, and therefore, the speed at which the instrument can be played.
The other category of air flow valves, as set forth above, relates to rotary valves, which typically include a valve disk which is provided at its periphery with air inlets and air outlets. These air inlets and outlets are generally disposed to communicate with one another through radial passages. Conventional rotary valves, generally of the type described, are for the most part highly regarded for use in musical instruments due to their quick action and relative simplicity of structure, as compared to the piston type valve. However, one distinct disadvantage associated with known, conventionally structured rotary valves is the unwanted addition of overtones to the sound of the instrument. Such overtones are considered to be the result of air passing over sharp bends existing along a flow path of the air as it travels through the instrument. These shape bends restrict the passage of air through the instrument and prevent a more desirable free and unrestricted air flow, which produces a pure and uniform tonal quality. In conventional rotary valve construction and design, the aforementioned sharp bends occur either inside the valve body or at the junction of the openings formed in the valve body and disposed between the valve body and the main tubing of the instrument itself. Further, when sound waves travel through an instrument and are directed along sharp turns or bends in the tubing of the instrument, a certain portion of the waves reflect off the inside surfaces of the air passage. Such partial reflection reduces the energy of the fundamental wave form and produces the aforementioned undesirable overtones.
Accordingly, there is a need in the musical industry for an improved flow regulating valve assembly for use on a musical instrument such as, but not limited to, a brass type of wind instrument. If any such improved valve assembly were developed, it should be capable of selectively varying the length of the path of air flow from the air inlet or mouth piece of the instrument to the air outlet or bell of the instrument, in order to provide the musician with a greater range of sound through a selective varying of the pitch of the instrument. In addition, if any such improved air flow valve assembly were developed, it should be configured, dimensioned and otherwise structured to provide a smooth, unrestricted air flow along any one of a plurality of air flow paths selected by the musician, thereby providing a desired tonal quality and allowing the musician to exert less effort when playing the lower notes. Further, any such improved air flow valve assembly developed should be adjustably mounted onto the musical instrument so as to facilitate removal of the assembly from the instrument for cleaning. Finally, any such improved air flow valve assembly would ideally also comprise either a single valve body or alternatively, a plurality of valve bodies, and could also be adapted for use in a variety of musical instruments such as, but not limited to slide trombones, baritone horns, euphoniums, tubas, french horns and trumpets as well as modern marching bugles.